| Message ID | 20220518031725.3128044-3-anshuman.khandual@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64/head: Cleanups for __create_page_tables() | expand |
On Wed, 18 May 2022 at 05:17, Anshuman Khandual <anshuman.khandual@arm.com> wrote: > > From: Mark Rutland <mark.rutland@arm.com> > > It's very easy to confuse __PHYS_OFFSET and PHYS_OFFSET. To clarify > things, let's remove __PHYS_OFFSET and use KERNEL_START directly, with > comments to show that we're using physical address, as we do for other > objects. > > At the same time, update the comment regarding the kernel entry address > to mention __pa(KERNEL_START) rather than __pa(PAGE_OFFSET). > > There should be no functional change as a result of this patch. > > Cc: Ard Biesheuvel <ardb@kernel.org> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will@kernel.org> > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Again, this conflicts with https://lore.kernel.org/linux-arm-kernel/20220411094824.4176877-1-ardb@kernel.org/ but the conflict can be resolved in a straight-forward manner. > --- > arch/arm64/kernel/head.S | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-) > > diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S > index 6a98f1a38c29..aaad76680495 100644 > --- a/arch/arm64/kernel/head.S > +++ b/arch/arm64/kernel/head.S > @@ -37,8 +37,6 @@ > > #include "efi-header.S" > > -#define __PHYS_OFFSET KERNEL_START > - > #if (PAGE_OFFSET & 0x1fffff) != 0 > #error PAGE_OFFSET must be at least 2MB aligned > #endif > @@ -52,7 +50,7 @@ > * x0 = physical address to the FDT blob. > * > * This code is mostly position independent so you call this at > - * __pa(PAGE_OFFSET). > + * __pa(KERNEL_START). > * > * Note that the callee-saved registers are used for storing variables > * that are useful before the MMU is enabled. The allocations are described > @@ -91,7 +89,7 @@ > SYM_CODE_START(primary_entry) > bl preserve_boot_args > bl init_kernel_el // w0=cpu_boot_mode > - adrp x23, __PHYS_OFFSET > + adrp x23, KERNEL_START // __pa(KERNEL_START) > and x23, x23, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0 > bl set_cpu_boot_mode_flag > bl __create_page_tables > @@ -420,7 +418,7 @@ SYM_FUNC_END(__create_page_tables) > /* > * The following fragment of code is executed with the MMU enabled. > * > - * x0 = __PHYS_OFFSET > + * x0 = __pa(KERNEL_START) > */ > SYM_FUNC_START_LOCAL(__primary_switched) > adr_l x4, init_task > @@ -870,7 +868,7 @@ SYM_FUNC_START_LOCAL(__primary_switch) > bl __relocate_kernel > #ifdef CONFIG_RANDOMIZE_BASE > ldr x8, =__primary_switched > - adrp x0, __PHYS_OFFSET > + adrp x0, KERNEL_START // __pa(KERNEL_START) > blr x8 > > /* > @@ -893,6 +891,6 @@ SYM_FUNC_START_LOCAL(__primary_switch) > #endif > #endif > ldr x8, =__primary_switched > - adrp x0, __PHYS_OFFSET > + adrp x0, KERNEL_START // __pa(KERNEL_START) > br x8 > SYM_FUNC_END(__primary_switch) > -- > 2.20.1 >
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 6a98f1a38c29..aaad76680495 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -37,8 +37,6 @@ #include "efi-header.S" -#define __PHYS_OFFSET KERNEL_START - #if (PAGE_OFFSET & 0x1fffff) != 0 #error PAGE_OFFSET must be at least 2MB aligned #endif @@ -52,7 +50,7 @@ * x0 = physical address to the FDT blob. * * This code is mostly position independent so you call this at - * __pa(PAGE_OFFSET). + * __pa(KERNEL_START). * * Note that the callee-saved registers are used for storing variables * that are useful before the MMU is enabled. The allocations are described @@ -91,7 +89,7 @@ SYM_CODE_START(primary_entry) bl preserve_boot_args bl init_kernel_el // w0=cpu_boot_mode - adrp x23, __PHYS_OFFSET + adrp x23, KERNEL_START // __pa(KERNEL_START) and x23, x23, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0 bl set_cpu_boot_mode_flag bl __create_page_tables @@ -420,7 +418,7 @@ SYM_FUNC_END(__create_page_tables) /* * The following fragment of code is executed with the MMU enabled. * - * x0 = __PHYS_OFFSET + * x0 = __pa(KERNEL_START) */ SYM_FUNC_START_LOCAL(__primary_switched) adr_l x4, init_task @@ -870,7 +868,7 @@ SYM_FUNC_START_LOCAL(__primary_switch) bl __relocate_kernel #ifdef CONFIG_RANDOMIZE_BASE ldr x8, =__primary_switched - adrp x0, __PHYS_OFFSET + adrp x0, KERNEL_START // __pa(KERNEL_START) blr x8 /* @@ -893,6 +891,6 @@ SYM_FUNC_START_LOCAL(__primary_switch) #endif #endif ldr x8, =__primary_switched - adrp x0, __PHYS_OFFSET + adrp x0, KERNEL_START // __pa(KERNEL_START) br x8 SYM_FUNC_END(__primary_switch)